Kevin Schawinski, Oxford / NASA / GALEX / Reuters

This ultraviolet flash of light was produced from inside this dying star just before it exploded. It marked the first time scientists observed what happened in the final moments before a doomed star burst into space.

ESA / NASA / AP

A pair of spiral galaxies found in the constellation of Hercules meet in a head-on collision in this new image from the Hubble Space Telescope. Fifty-nine new swirling galaxy images from the famed telescope were released on April 24 on the 18th anniversary of its launch.

NASA / AP

Even galaxies get bullied. Here, a so-called "death star galaxy" blasts a nearby galaxy with a jet of energy. Scientists said that if this happened in the Milky Way, it would likely destroy all life on Earth.

ESA / MPS / DLR / IDA

In February, photos taken in July 2007 were released showing a puzzling haze that brightened and dimmed over Venus' southern latitudes. The haze moved toward the equator and then back to the south pole. Scientists aren't sure what is causing it.

NASA / Getty Images

In 2005, NASA's Hubble Telescope captured this image of the Crab Nebula, a six-light-year-wide expanding remnant of a star's supernova explosion. Japanese and Chinese astronomers witnessed this violent event in 1054.

JPL-Caltech / NASA / AP

For years, astronomers have been baffled by the source of antimatter. Now, researchers say the matter-annihilating material is generated when stars get ripped apart by black holes or neutron stars. In this image from NASA's Spitzer Space Telescope, thousands of stars swirl around the supermassive black hole at the center of the Milky Way.

JPL-Caltech / NASA

Feel like you are being watched? This infrared image from NASA's Spitzer Space Telescope shows the Helix nebula, a cosmic starlet notable for its vivid colors and eerie resemblance to a giant eye.

JPL-Caltech / NASA

The Cassini spacecraft's 2005 flyby of Saturn's moon Hyperion revealed its sponge-textured surface. This image was colored to bring out the surface's details. Hyperion has a notably reddish tint when viewed in natural color.

STScI / ESA / NASA

This star is ending its life by casting off its outer layers of gas, forming a cocoon around the star's remaining core. The burned-out star, called a white dwarf, is the white dot in the center.

NASA / AFP / Getty Images

Though Jupiter looks like it has a mild case of the measles, the five spots scattered across the upper half of the planet are actually a rare alignment of some of Jupiter's moons and the shadows they are casting.

ESA / NASA

Here, bright blue newly formed stars are blowing a cavity in the center of a star-forming region and eroding the outer portions of the nebula, with numerous galaxies delivering a grand backdrop for the stellar newcomers.

ESA / NASA / AP

This small open star cluster lies in the core of the large emission nebula in Sagittarius, about 8,000 light-years away from Earth. Some of the stars in this cluster are extremely massive and emit intense ultraviolet radiation.

Hubble Heritage Team / ESA / NASA

This is one of the largest panoramic images ever taken with Hubble's cameras, a 50-light-year-wide view of the central region of the Carina Nebula where a maelstrom of a star's birth and death is taking place.

ESA / NASA

These are views of an unusual phenomenon called a light echo. Light from an erupted star continues outward through a cloud of dust surrounding the star. The light reflects or "echoes" off the dust and then travels to Earth.

Carnegie Institute / JHU / NASA

Scientists got a good look at Mercury for the first time since 1975 when NASA's MESSENGER probe beamed back 1,200 new images of the planet closest to the sun.

NASA / Getty Images

This eerie-looking Eagle Nebula, a tall, dense tower of gas, is one of three-quarters of a million photos of the cosmos taken by the Hubble Telescope.

NASA / Getty Images

This image of the Whirlpool Galaxy is one of the sharpest Hubble has ever produced. The telescope has orbited the Earth for 15 years and has taken more than 700,000 images of the cosmos.

NASA / AP

A volcano on the north pole of Jupiter's fourth largest moon, Io, spews a giant plume of dust 200 miles into space.

Hubble Heritage Team / NASA

This is one of the universe's most photogenic galaxies, the Sombrero Galaxy. Its hallmark is a brilliant white, bulbous core encircled by thick dust lanes comprising the spiral structure of the galaxy.

NASA / AP

Resembling the fury of a raging sea, this is actually a bubbly ocean of glowing hydrogen gas and small amounts of other elements such as oxygen and sulfur within the Omega or Swan Nebula.

Johns Hopkins University / ESA / NASA

This ghostly ring is strong evidence for the existence of dark matter. Although astronomers cannot see dark matter, they can infer its existence by mapping the distorted shapes of the background galaxies.

JPL / NASA

This dramatic shot of the Orion Nebula offers a peek inside a cavern of roiling dust and gas where more than 3,000 stars are forming.

Dan Bayer, The Hutchinson News / AP

Comet Hale-Bopp passes over a rural Rice County, Kan., windmill, just north of Hutchinson, Kan., on Thurday, March 27, 1997.

STScI / ESA / NASA

The Hubble Space Telescope "caught" the Boomerang Nebula, which is a reflecting cloud of dust and gas with two nearly symmetric lobes of matter that are being ejected from a central star.

NASA / AP

Astronomers have confirmed the presence of two new moons around the distant dwarf planet Pluto. Here, Pluto is in the center and Charon is just below it. The moons are named, from far right, Hydra and Nix, respectively.

NASA

This nebula is the glowing remains of a dying, sun-like star. This stellar relic is called the Eskimo Nebula because, when viewed through ground-based telescopes, it resembles a face surrounded by a fur parka.

ST-ECF / ESA / NASA

A pair of huge interstellar "twisters" -- eerie funnels reminiscent of terrestrial tornadoes -- are seen in the heart of the Lagoon Nebula about 5,000 light-years from Earth.